Dynamic Decoding of Binaural Audio Signals

Abstract

Inputting of a parametrically encoded audio signal comprising at least one combined signal of a plurality of audio channels and one or more corresponding sets of side information describing a multi-channel sound image and including channel configuration information is shown along with deriving, from the channel configuration information, audio source location data describing at least one of horizontal and vertical positions of audio sources in the binaural audio signal; selecting, from a predetermined set of head-related transfer function filters, a left-right pair of head-related transfer function filters matching closest to the audio source location data, wherein the left-right pair of head-related transfer function filters is searched in a stepwise motion in a horizontal plane; and synthesizing a binaural audio signal from the at least one processed signal according to side information and the channel configuration information.

Description

BACKGROUND OF THE INVENTION[0001]The present invention relates to spatial audio coding, and more particularly to controlling dynamic decoding of binaural audio signals.[0002]In spatial audio coding, a two / multi-channel audio signal is processed such that the audio signals to be reproduced on different audio channels differ from one another, thereby providing the listeners with an impression of a spatial effect around the audio source. The spatial effect can be created by recording the audio directly into suitable formats for multi-channel or binaural reproduction, or the spatial effect can be created artificially in any two / multi-channel audio signal, which is known as spatialization.[0003]It is generally known that for headphones reproduction artificial spatialization can be performed by HRTF (Head Related Transfer Function) filtering, which produces binaural signals for the listener's left and right ear. Sound source signals are filtered with filters derived from the HRTFs corresp...

AI Technical Summary

Benefits of technology

The invention provides a method for making dynamic binaural control available even if the decoder contains only a limited set of HRTF filters. The method involves inputting a parametric audio signal and generating a binaural audio signal by searching a set of head-related transfer function filters in a stepwise motion. The method allows for a minimization of the bitrate of control information and reliable utilization of dynamic control. Additionally, the invention provides a method for generating a parametric audio signal by inputting a multi-channel audio signal and generating corresponding side information including channel configuration information for controlling audio source locations in a synthesis of a binaural audio signal. This allows for control of the use of incremental steps in the binaural downmix.

Problems solved by technology

Therefore, the content creation does not have any knowledge on the available HRTF filter database in the binaural decoder.

As a result, the decoder may omit the audio image control due to an incompatible HRTF filter set, whereby the perceived audio image may differ significantly from what was intended by the content creator.

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